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Do Landings in a Simulator Count Towards Landing Currency? (FAA in the USA)
If a pilot is trying to complete 3 day or night landings every 90 days in a multi-engine aircraft in order to be multi-engine current per FAA requirements, can those landings be done in a Simulator or a Flight Training Device?

Related: http://aviation.stackexchange.com/questions/8966/is-it-possible-to-log-ifr-currency-in-a-flight-simulator-without-an-instructor

An FTD? No... With a full motion sim that airlines use? I think it can, but I'm not sure.

@Federico this question is more specific, and to be honest the answers in that question aren't great quality (just referring to an external source)... I'm tempted to leave this question open in hopes of a more complete answer

Yes, as long as the simulator is properly certified (to level B,C,or D) you can do your takeoffs and landings to regain currency.
Long haul airline pilots frequently have trouble staying current for 3 takeoffs and landings in 90 days. This is because it takes 4 pilots to complete a long haul flight but only 1 will get the takeoff and landing.
3 trips a month is about all you do, and if you are scheduled to be the augment pilot, you don't get a takeoff and landing.

According to this: http://d.pr/i/1aw7o it can be a level B, C, or D simulator. Thanks!

Good find. You are correct. I edited my answer to say B, C, or D. Thanks.

It can be done. As mentioned here:

(2) The takeoffs and landings required by paragraph (b)(1) of this
  section may be accomplished in a flight simulator that is—
(i) Approved by the Administrator for takeoffs and landings, if the
  visual system is adjusted to represent the period described in
  paragraph (b)(1) of this section; and
(ii) Used in accordance with an approved course conducted by a
  training center certificated under part 142 of this chapter.

The regulation is 14 CFR 61.57. For more details, you can read this AC.


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What was the first fighter jet that utilised thrust vectoring nozzles?
What is the first fighter jet that utilised thrust vectoring nozzles?

I would bet on some crazy Nazi design.

Wikipedia: "A design for a jet incorporating thrust vectoring was submitted in 1949 to the British Air Ministry by Percy Walwyn. Official interest was curtailed when it was realised that the designer was a patient in a mental hospital."

@RonBeyer That so needs to be an answer ...

Hawker harrier... (actual plane that got used)
https://en.wikipedia.org/wiki/Hawker_Siddeley_Harrier

This answer would be better if substantiated with links or sources.

absolutely... added link.

Although not a fighter, the prototype of the A-6 Intruder (YA2F-1) had tilting nozzles which were removed at some point after the flight testing had begun. There is a pretty nice photo of it in the A-6 Intruder article on Wikipedia, but for some reason I can't paste the link into the comment.

Surely this should be the Hawker Siddeley P.1127 / Kestrel ?

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Would it be possible to build a "rocket" using a series of ducted fans?
I'm wondering if it would be possible to build ducted fan "rocket".
My idea is to construct the duct from 18650 batteries, and to have a series of contra rotating fans along its length.
I can 3d print new blades to have a steeper angles as the air-flow/speed increases.
This is the fan I'm looking at.
A 90mm fan will let you make a ring of 16 batteries around the curcumference and it would be 6 batteries tall as it's a 6s motor.
Is this feasable/will it work? what kind of thrust would I get?
Here is a quick render I made:

Welcome to av.se. Not sure that this question is really on-topic here; may be better suited to a different stack exchange forum. Looks like an interesting project, though.

By stacking the fans like that, you're going to get way less thrust than what you are expecting.

That would probably be one of those things you have to file under the category of “well you could - but why would you want to?”

I want a platform on which to build/test a rocket flight computer & control system, launch - short ballistic flight - landing.
I want to mimic what you get with real rockets - have the bottom fan gimble (5~10 degrees) and stablize it with thrusters near the top (divert air-flow from the top fan).
I realize its not gonna have 4x the thrust, I'm just wondering how much I'll get with this design assuming the blades are optimised etc.

@CarloFelicione "Why would you want to" is not a question that OP needs our help for in answering.

With enough engineering you could probably get some fewer stage variation of this idea to fly to a degree, but it wouldn't really mimic the challenges of controlling the boost phase of a rocket.

You may not need a series, a single fan can do it: https://www.youtube.com/watch?v=_kd64VE3A1c

yeah I saw that video, the thrust to weight ratio is weak, I'm planning something with a lot more power.

From the link you provided:

Specification:

Rotor Diameter: 90mm

Fan blades:11 blades
Weight: about 350g
Working Voltage:6s(22.2V) lipo battery
Motor:Brushless Motor 3553 1450kv
No Load Current: 4.1 A
Load Current: 83A
No Load Speed:32190 rpm
Load Speed:16095 rpm
Thrust: 3300g
G/A:45.16

Assuming that 16 * 6/4 = 24 cells of type 18650 would be able to deliver full electrical power for the fan, the issue would indeed be the local angle of attack of the fan blades.
Thrust at full power is listed at 3.3 kg = 32 N. This would be at standstill/hovering conditions at sea level, since measuring at that level provides the highest thrust level for advertisements. Diameter is 0.09m. Net thrust T =
$$ T = \dot{m} \cdot (V_{out} - V_{in}) = \dot{m} \cdot \Delta V \tag{1}$$
$$ \dot{m} = \rho \cdot A \cdot V \tag{2} $$
Combining (1) and (2) for the hover, with $V_{in}$ = 0:
$$ V = \sqrt{\frac{T}{\rho \cdot A}} = \sqrt{\frac{32}{1.225 \cdot \pi/4\cdot0.09^2}} = ~\text{64 m/s}$$
Impulse thrust considerations usually draw a contracting propeller wake for inducted propellers. Ducted fans work a bit differently and we can take the average velocity behind the fan for further Order Of Magnituding. Below figure is from this research paper, and shows the considerations for ducted fan flow; it contains some methods for more detailed computations.

Rotational speed under load is 16095 rpm = 1,684 rad/s, tip speed = 0.045 * 1,684 = 75.8 m/s. A velocity triangle at the blade tip has as angle $ tan^{-1} (64/75.8) = 40 $ deg. The blade needs to be inclined further than that, usually about 6 deg, so tip blade angle of the standard fan would be 46 deg. Purchasing the actual fan for verifying the above would be a good thing!
For the second fan, this same method can be followed: mass stream will remain the same if the hull is closed, in order for the 2nd fan to deliver the same thrust $\Delta V$ = 64 => ${V_{}out} = 64 + 64 = 128 $ m/s. Tip angle velocity triangle = $ tan^{-1} (128/75.8) = 59.4 $ deg, fan blade angle = 59.4 + 6 = 66 deg, etc.
Note that the above is valid for the hover. As soon as the "rocket" picks up speed, the local angle of attack of the fan blades will reduce and therefore thrust will reduce. So one would have to optimise time of thrust (time of amps delivered) with weight, momentary speed, and expected end speed, then average the blade angles out for the speed function.
Note that opening the hull in between the fans allows for extra air to be drawn in, increasing the mass flow. The paper cited above has results for a setup like that as well - if the increased mass flow relates in lower entry velocity, this might be worth considering.

wow, thanks for the great answer! I'm pleased to hear this is feasable.
I may scale back to just 2 fans & 48 cells initially, but leave space for the full design.
I don't really understand all the technical stuff, I was just gonna try out a range of different blade angles but I'll be sure to make some around 60 deg.
If the thrust is good enough, I could even optimise them closer to forward flight.

Blade pitch: the first fan is whatever the manufacturer has set it to to get 32 N of thrust, the second one needs a higher pitch, the 3rd one even higher, and the 4th one still higher. Best to verify my computation of 45 deg of the first blade pitch, then the above method for each subsequent fan blade pitch can be followed.

And then: establish total thrust at lift-off. Determine the current draw, and how long the cells can sustain this (function of amps over time gives a function of thrust over time). Compute the resulting acceleration and velocity as a function of time, and adjust the blade pitches such that the highest end velocity is reached at the end of cell life. Best done with a numerical solution, a real-time simulation of all the physics. Mathworks might be your friend here. I'm sadly lacking the time to do it at the moment.

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How are CPDLC VHF messages transmitted between ATC and aircraft?
I'm trying to read up on some of the new developments in ATC (ATN, FANS etc.) and I've come across CPDLC: Controller–Pilot Data Link Communications. In particular, I'm confused of how the VHF messages travel to and from Air Traffic Control and the aircraft.
For the oceanic/remote flying, transmitting messages over SatCom sounds entirely reasonable. But everything I can find on VHF seems to imply that they use a separate Datalink Service Provider, similar how ACARS functions.
I always thought ATC had a bunch of antennas on the tower roof to do voice VHF. If this is the case, what prevents ATC from having their own datalink transceiver and doing all of this stuff 'in-house', avoiding more parties and infrastructure?

It's not impossible the VHF equipment on the tower is part of the GCN visible in the picture, but it seems there is this requirement: "the communication network must “always” be available and interruptions are “not” acceptable" which makes a single receiver solution unusable and a network mandatory (source). On the other hand ATC voice channels are also going digital, which makes a new (digital) solution potentially more valuable.

For non-oceanic operations, aside from the tower radios, most ATC communications go through remote communications outlets (RCO) scattered around to get the necessary coverage.  most are co-located with VORs or other navigational aids.  The controllers are located in either a TRACON or Center facility that's often a long distance to the RCOs.
The problem is this equipment is these systems were designed for voice comm (double-side band AM radios).  For data link, the radios operate as a radio modem using VHF data link (VDL) Mode 2.  So three things have to happen: 1. the controller needs a data link enabled workstation, 2. there has to be a network connection to the RCOs, and 3. the radios need to support VDL mode 2.
So the real issue boils down to the two primary factors; time and money.  The implementation in the US is part of Nexgen.  To speed up the implementation, there is the alternative of leasing services of network providers such as ARINC and SITA.
BTW, the most comprehensive reference on data link is the Global Operational  Data Link Document.


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How is collision avoidance regulated in controlled airspace in Canada?
According to CAR 302.31(3) "Compliance with Air Traffic Control Instructions and Clearances"

The pilot-in-command of an aircraft may deviate from an air traffic control clearance or an air traffic control instruction to the extent necessary to carry out a collision avoidance manoeuvre, if the manoeuvre is carried out

(a) in accordance with a resolution advisory generated by an ACAS; or
(b) in response to an alert from a TAWS or a Ground Proximity Warning System (GPWS).

I know that even in controlled airspace with separation/conflict resolution, and without equipment mentioned in (a) and (b) it is the responsibility of the pilot to avoid collisions. Is that covered by a different CAR?


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When to log time as PIC, Dual or Co-Pilot?
I'm currently finishing up my Canadian PPL. I have questions around logging my time appropriately.
Most of it is pretty straight forward. Looking at 401.08 the only thing I'm unsure about is how to log (c) the flight crew position in which the holder acted;
I have a "Pilot Logbook" from VIP Pilot Centre. I'm not using it as I'm maintaining my log online but I use it as a template. It distinguishes between the following three roles: Dual, PIC and Co-Pilot.
Here's how I interpret them:

Dual: during instruction, when CFI is PIC
PIC: student solo flight / solo flight once I hold my PPL

What about Co-Pilot. Is that only relevant when acting as co pilot in an airplane that requires two pilots? What about if, once I have my PPL, I fly around in a C172 with a friend as the PIC, can I log that as Co-Pilot time?

Only a required crew member or an instructor can log time, so no. But if your friend was PIC and in simulated instrument conditions, you (as lookout) would be a required crew member but neither PIC nor sole manipulator of controls, so could log second in command time.

Canadian law is as follows:
At no time can anyone in a private C172 log SIC or co-pilot time, because the 172 is certified only for single pilot operations and the aircraft is not flown under the provisions of an Operating Certificate that mandates two pilot operation.
You can log dual (instruction) time when you are receiving instruction from a Flight Instructor certified to do so. (In Canada CFI refers exclusively to the Chief Flight Instructor of a Flight Training Unit.)
Otherwise, you can log PIC time, when you are PIC, otherwise you cannot log time at all.
If you are in simulated IMC, either you or your friend can log time, assuming you are both qualified to be PIC, and depending on who you agree between you is Pilot In Command, but never both of you, unless he is a qualified flight instructor. Even then, only one person can log PIC time, in Canada.
Note that in Canada it is not required for the "lookout" or "safety person" to be a qualified pilot of any kind, if the PIC wants to fly under the hood. It remains the PIC's responsibility to fly safely and look out for traffic, and he or she can discharge that responsibility by asking any responsible person to help them.
These rules are rather different from the ones that prevail in the US.
Hope that helps!

Does Canada not allow a safety pilot to log SIC time despite being a required crew member?


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What are the consequences of pumping the throttle in an carburetor piston engine airplane during start?
I have seen an expert commercial pilot pumping the throttle during start for a Cessna 152 and ever since I thought that was ok to do so, but recently studying for ATPL I read about that these technique can produce a risk of engine fire during start. What are the consequences of such a start on short or long term on the engine?

I have read many times about the correct technique on the POH of the airplane but since I seen a much expert pilot I thought that could be an alternative way during cold operation.

I’ve been told that it is more dangerous to do in a Piper than a Cessna due to (I think) the position of the accelerator pump. I hope someone can give a good informed answer.

Pumping the carb during a cold start, in an updraft engine such as the 152 has, is the #1 cause of engine fires, and can be eliminated by the proper and factory recommended starting procedure.
The correct procedure is to prime, then open the throtte about 1/4" and then crank the engine.  All planes vary, especially if the primers are varnished up to one degree or another, but here is some guidance for a 152 and 172:
10C  - 1 full pump of primer
0C   - 2 pumps of primer
-10C - 3 pumps of primer
-20C - 4 pumps of primer, however the engine should be preheated prior to starting at this and colder temperatures.
Using the primer, puts a charge in either one or all cylinders, which is adequate to compensate for carb fuel/air mix being condensed on the cylinder walls at the ambient temperature.
Using the throttle pump to enrichen the mixture sprays a little squirt of fuel into the carburetor. If the engine is not running, much of that fuel drips downward out of the "bottom" or inlet side of the carburetor.  Too much (easy to do) will drip out, and load the inlet box, and can also drip to the ground.  If the engine has even a small backfire, it may ignite the additional fuel there, which will rapidly heat up the carb which has an ample supply of more fuel.
If you can't start with the primer, it is likely that the primers are varnished up and need to be cleaned by a mechanic.  They come out, similar to spark plugs.
Also in the 152, you may have a primer on #1 or on all four cylinders. It largely depends on where the plane was initially delivered.  If a colder climate, the plane would likely have come with four primers.
Cold addendum #1:  It is acceptable on most engines to pump the primer when starting in extreme cold.  The way I do this, and normally for -20C and colder starts, is to leave the primer out, and pump it firmly in as the engine starts to fire. Generally no more than three pumps in C172 and C182 aircraft.
Generally, the primer injects into the cylinder, whereas the throttle pump uses the accelerator pump, which injects into an updraft carburetor. It is that large amount of fuel dribbling down the updraft carburetor which creates the starting fire risk.
Again engine configurations vary, and I would talk with a mechanic familiar with cold weather operations to refine your starting procedures.  But on aircraft that I have regularly flown, starting at -20C and -30C temperatures is rather routine if your equipment is properly operating, and the crew is properly trained.

I noticed the fuel dripping out of the carb when I moved the throttle back and forth to lubricate the throttle cable. There was a surprising amount of fuel on the floor for just a few pulls on the throttle.

Yes, and you were lubricating, rather than pumping to start an engine.  There was one instructor who refused to use primer and insisted that he pump the throttle.  Over almost two decades, he toasted two planes. A couple of pumps (4) can give you 1.5 to 2 oz of gasoline...in the wrong spot. The manufacturer installed a primer for a reason.

Also, something not everyone is informed on.  Many trainers and 4 cylinder planes come with two flavors of primers: a single primer, normally shipped to warm locations and a primer on every cylinder.  The latter is obviously preferred, and at temps of -10C can make a big difference.


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What is the procedure after a missed approach at the destination alternate since alternate fuel does not contain a missed app. at the alternate?
I am currently studying the fuel policy planning criteria for ATPL EASA(A) and i just learnt that the alternate fuel does NOT comprise the missed approach at the alternate destination aerodrome; in case of such a situation and without contingency fuel (imagine that is already used during trip), what is the procedure then since that I probably have to use the final reserve fuel? I guess that I should declare an emergency, how would it be declared?

This scenario highlights the importance of selecting an alternate where a successful approach is certain. It is not a formality.

Let's assume you started exactly with ICAO minimum fuel required (as explained in What are the ICAO fuel reserve requirements?):

Taxi fuel Let's assume you used all of it at your departure airport.
Trip fuel Used for the flight to the destination airport.
Contingency fuel Let's assume this was used in a holding pattern at the destination.
Alternate fuel Used for a go around at the destination and the subsequent flight to the alternate airport.
Final reserve Not used yet.
Additional fuel Let's assume you did not take any.

Under these assumptions you would be using the Final reserve fuel for your go around at the alternate airport. At this point you should declare an emergency (see Do I have to declare an emergency if I cut into fuel reserves?) by broadcasting

MAYDAY, MAYDAY, MAYDAY, FUEL

as explained in What is the correct phraseology for declaring a fuel emergency?. ATC will then assist you to get to any suitable airport as soon as possible.

This is fully the pilot responsibilities; if he has a fuel quantity problem, or if he believes that again a missed approach may occur, prior to commencing the alternate approach, he must make a specific request to ATC in the event that one occurs. Such a request may include heading and altitude instructions to avoid in-flight delays (such as holds) and efficiently maneuver the aircraft into position for the next approach.

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What is the difference between a functional check and an operational check?
Can anyone explain what is the difference between a functional check and an operational check in aviation?
Basically I faced a problem to prepare the task card for functional and operational check of a FDR (Flight Data Recorder).

I've only ever done aircraft maintenance in the UK military.  I have no idea if this will help or hinder.  Functional testing was conducted before flight after maintenance.  It answered the question "does the component basic functionality work?" This might include BITE (automated tests, "Built In Test Equipment) and testing with dedicated test equipment.  A given component might also need an operational check which was an item added to the next flight plan to confirm the component in airborne use or operated with all other related systems together.

In other words, a functional test only verified the component.  An operational test confirmed it's working within the overall system.  An example would be a GPS receiver.  Functional test - does it lock on, acquire and display a good location fix.  Operational test - does it successfully and accurately feed the FMS for flight progress calculations?

From the ATA spec 100 which is the standard for aircraft maintenance documentation, they provide the following definitions:

(c) Following are definitions of three categories of test that shall
  apply:
1 Operational Test
a.  That procedure required to ascertain only that a system or unit is
  operable. These tests should require no special equipment or
  facilities other than that installed on the aircraft and should be
  comparable to the tests performed by the flight crews. It is not
  intended that the operational test of the unit shall meet the
  specifications and tolerances ordinarily established for overhaul, or
  major maintenance periods.
2 Functional Test
a.  That procedure required to ascertain that a system or unit is
  functioning in all aspects in accordance with minimum acceptable
  system or unit design specifications. These tests may require
  supplemental ground support equipment and should be more specific and
  detailed than an operational test. It should contain all necessary
  information to perform proficiency tests to maintain system or unit
  reliability at an acceptable level, without reference to additional
  documents.
3 System Test
a.  That procedure containing all adjustment specifications and
  tolerances required to maintain system and/or unit performance at
  maximum efficiency and design specifications. It shall be
  self-contained and may duplicate other tests. It is normally used at
  major maintenance periods.

I would expect that these definitions are pretty universal in aviation.


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How do I find how much it costs to park a B747 at an airbridge in Perth?
I need to park my B747 at Perth for 1 hour. How much will it cost me? You may assume I have 200 fare paying passengers. I must use an airbridge for those 60 minutes.
To be honest, I don't really own a B747 (yet), but am having trouble figuring out the costs for this. I've found some example costs for various airports around the world, and some landing fee documents on the airport's site, but they're a trifle confusing to decipher.
Perth's commercial fees appear to be here.

Related: How do airports charge airlines for using their gates?

Starting an airline? That's interesting! Need pilots? Drop me a message!

Outside of a Japanese domestic shuttle, one hour is a pretty fast turn around for a B747.

Note that parking is not the same as waiting at the gate to load/offload passengers. Parking is when your aircraft is not using the terminal, but the airport facilities (like aprons, hangars, etc.)
Let us assume you are carrying 200 passengers, and leaving with 200 passengers:
First of all, you have to pay the landing fee, which is:
(4.891 x 400) + (9.528 x your landing weight, in tonnes)
Next, you have to calculate the terminal charges - assuming you are an international flight, (so you are using Terminal 1):
(13.868 x 400) + (0.450 x 200) + (1.111 x 200) + (5.997 x 200)

13.868 is the terminal fee, per arriving or departing passenger
0.450 is Common Use Service charge, per departing passenger
1.111 is the security fee, per departing passenger
5.997 is the baggage checking fee, per departing passenger

Since you'll only be staying for 1 hour, you don't have to pay any parking charges; which are only charged for staying more than 2 hours.
So total passenger fees are: AUS $9,015.20, before tax;  you still have to calculate your landing weight and multiply it by 9.528 to get the final amount.

Is it possible there's a decimal point in the wrong place? I can't see any airline managing to make a profit with costs of AUS$20k per passenger.

Ah, you have a point. Maybe in AUS the . is not a thousands separator?

Terminal charges are $13.868 is just under $14 per passenger. Total passenger fees will come to ~$9k not ~$9M.

Corrected, thanks.

@BurhanKhalid In English, the thousands separator is a comma; the decimal separator is the period.

Can you share a source for where these numbers came from?

@fooot Those figures come from the link in the question which links to a PDF from the Perth Airports Corporation website.


text:
What is that term to describe the wing motion range?
What is that term naming the range of motion of the wings when on the ground (hanging/drooping) then bends upwards during flight?

Wing flex is the term you're looking for.

The term that you are looking for is Wing Flex. The extent of flex is a product of the material.The wing needs a stated definitive strength. With metal, that transforms into a given amount of flex. IOW, the flex, is basically just a by-product of the materials and high aspect ratio design and is not a design goal in itself. The benefit is, smooth ride during a turbulence.
Aerodynamically you do pay a penalty. However, to a certain extent this will be offset by lighter weight and the much superior strength, facilitates the high aspect ratio which more than make up for the loss due to the flex.

I came across that word once on the internet and couldn't find it again.  It starts with the letter "b".  Wing flex is probably one of the more common reference to it but that is not the word I'm trying to remember.

@DannLogue Ok. In that case I suspect you'll have to re word your question so that it captures the exact type of movement that you are referring to. My answer above is based on the question that you have asked. If the above answer is not of any help, please let me know if I should delete it. Thanks.


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Are there limitations in US legislation on a US citizen to own a MiG-15 in Europe?
If US citizen buys cold war era MiG-15 jet fighter aircraft, which:
- had been acquired from the museum (facility of the Ministry of Defense one of the European Union countries, member of NATO) by private person (contract document is available);
- is still located in that country;
- at least for time being the plane will stay located in that country even after the US citizen buys it from that private person;
Now, since that US citizen is also dual citizen of that country:
- Is there anything which he needs to do to be in compliance with US law?
- Is there anything which he should not do to be in compliance with US law?
- Or, since the plane will stay in that country (no import/export will take place), is everything basically governed by that country law only and he is good just to stay in compliance with the law of that country?
Does the same apply to any weapon/armament accessories present like cannons, gun camera, gun sight, ejection seat? E.g. cannons are now independently stored at the third party, licensed to handle military material. He would not get cannons to his possession until unless they are modified (deactivated) according to the law of that country.

This is really something you need to work with an FSDO on, importing or registering a demilitarized jet is a complicated process.

Hello Ron, thank you, but NO import/export/registering will take place, plane will stay in Europe. I just want to know if pure owning does not break any US law...

While this is aviation-related, you might get a better answer on law.SE because you're asking a fairly complex question about legally owning something abroad that might be illegal in the US. And there's the dual citizenship point, too, which could complicate things (or not, I have no idea).

With mere possession the only issue you might run into is any live, functional weapons on the aircraft. This is governed more by the nature of the device than the person owning it. Generally speaking, Europe is far less accommodating regarding private citizen ownership of military weapons than the US, especially nasty ones like automatic cannons. If they have been demilled to the specifications of the country in which they reside, then they're not guns any more, just decorations.
A couple of years ago, I saw a Soviet era MI-24 attack helicopter for sale in the US. Main and tail rotors present, no engines, no weapons, cockpit was pretty much gutted, airframe was past its useful life, for static display only. It looked intact from the outside... and also looked very sinister. For some odd reason, my wife balked at me spending $8k on this ultimate lawn decoration. But, there were no regulations regarding its ownership, other than maybe a neighborhood association getting huffy about someone parking an attack helicopter in their front yard.
Now, if you want to actually fly the MIG15, that's a different matter. But if you as a US citizen want to purchase a MIG15 as a static display, without functional weapons, the only thing the US government is going to care about is whether you paid their income tax on the money you use to buy it.

Thank you. Any other opinions on the matter from the experts are more than welcomed...

It is legal for FAA registered/US Owned planes to be kept in Europe and due to regulations its done fairly often. As for owning a Mig-15 as long as its kept airworthy you should be fine. I even see some for sale here in the states. You don't need to physically import the plane for it to be US owned and Registered.
As for the legality there are some things you need to keep in mind

The aircraft must be owned by a US entity or individual
You must have an pilots licensed by either the FAA or the local country
The plane will need to be inspected according to the FAA regs. You will most likely end up needing to find an FAA IA to sign off on stuff in Europe. They do exists but expect to pay a premium to keep the plane flying.

As for the weapons on board, the simple answer is, don't bother messing with that. The EU's gun regulations tend to be far stricter than here in the US. With the exception of California's ban on the .50BMG round there really is no caliber limit here in the US and with proper paperwork you can own pretty much anything you want. With that in mind you could legally own the guns that would come on the plane here in the states but as to if you can fly with them is a completely different question. You can not militarize an aircraft so keeping the guns on the plane is out of the question. FWIW if this is something you are looking into its worth it to have the current owner strip all this kind of stuff out prior to your purchase.

"you can not militarize", but does that include owning something that was "militarized" when purchased... Interesting idea, might have a loophole there. Another thing to consider is that it might not even be legal to own and operate the MiG in the EU when in airworthy condition, armed or not. I don't know EU aviation law and regulations well enough, but it might well be that the aircraft lacks the documentation at individual or type level to allow civilian operation, in which case it's not legal to fly it in the EU and the only way to ship it out would be on a truck or barge.

@jwenting yes I presume that includes already militarized jets here in the states. Legally you are operating under FAA regs for airworthiness so im not sure how the EU stuff applies over that. You would need any physical equipment (transponders etc) required for their airspace but would be operating under FAA airworthiness regs. A lawyer is a good idea in this case.


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How are GA aircraft ferried from factories?
It's relatively easy to transport jet aircraft like Airbus and Boeing: most of them have a long range, and a few hops at most would get them to the owner.
But how would a Cessna manufactured in U.S. be delivered to Dubai? It would not have the range to cross the Atlantic. Taking a brand new single-engine aircraft across a large ocean also sounds very risky (to the occupants). Same story applies to Hawaii.
Getting there may also require many hops (e.g. Texas -> California -> Canada -> Alaska -> Japan -> Taiwan -> Singapore), making the transportation long and costly.
Are they put on trailers and shipped like cargo? If yes, how is the aircraft taken apart? (I'd imagine even the wing span of a 172 would be too wide for roads in many countries)

EDIT: the linked question addresses airliners. I am specifically interested in GA airplanes.

possible duplicate of How do airliners get from the factory to the client if the aircraft does not have the required range

I found this today; it's a video of a Cessna being delivered from California to Poland.
https://www.youtube.com/watch?v=kp_qVXNZInQ

wild guess: by plane? perhaps a small airplane could fit into an AN-124

As you've guessed, there are two options: a ferry flight, or shipping the aircraft in a container.
Ferry flights are quite common; the recent Cirrus ditching in the Pacific was a ferry flight to Hawaii. As well as planning a suitable route and dealing with permits and paperwork, refueling etc., the ferry company may install extra fuel tanks to give more range, and provide the pilot with specialized survival and communications gear. And an airline ticket home, of course :-) This might all seem expensive, but considering that a new top-of-the-range Cirrus SR22 has a list price of almost USD 800,000 you can imagine that ferry costs aren't necessarily a big deal in comparison.
The second option is to put the aircraft in a container and ship it, and there are some companies who specialize in this (the page has some small photos of aircraft in containers). The major concern in this case is removing the wings: gliders and many experimental (e.g. home-built) aircraft are designed to have their wings removed for storage and transportation (towing behind your car) but most typical Cessnas, Beechcraft etc. aren't. You need to have the aircraft professionally and carefully prepared and then re-assembled and checked after delivery.
Which option is best depends on the costs of each option and the value of the aircraft. There's also the consideration that if you buy a 60-year old aircraft from the other side of the world, ferry companies may decline to fly it to you because of the risks of subjecting it to the stresses and weather of a very long series of flights. Or their/your insurance company may refuse cover for a ferry flight for the same reason. Or perhaps the aircraft is certified for VFR only, which would make a long ferry journey much more difficult to plan and execute. In those cases, container shipping may be the only available option.

Your "extra fuel tanks"-link is pointing to a non existing site (error 404): http://www.turtlepac.com/products/collapsible-aircraft-ferry-tanks.html

@jklingler Thanks! I replaced it with a link to Wikipedia, which should be better

Question: Does the fuel from the extra tanks get pumped into the wing while in flight? Or is the tank somehow connected with the engine and feeds it directly?

@jklingler I have no idea, that could be a good question to ask. I guess it depends on the aircraft type and what's physically possible without major alterations. And what a regulator will approve, of course.

You can often get to Reykavic airport in Iceland for crossing the Atlantic.
If that hop is still too far you can install extra fuel tanks in the cargo hold and/or passenger area temporarily.

Transatlantic ferry flights often stop at CYQX, BGBW and/or EGPC as well.

I can't tell you, if this applies to Cessnas or not, but at least some of the lighter planes are simply shipped by ship or cargo planes. They take those apart. Not completely of course, but they take off the wings and tail. Once they are arrived, they put them back together or leave that part to the new owner.
I don't know whether this applies to all or some planes, but at least my boss's was transported this way. He went to Rotterdam to pick it up.

"He went to Rotterdam to pick it up." doesn't really mean much with no idea where your boss normally lives. That could be the next town over, or several countries away.

@MichaelKjörling You're right. To clarify: He lives in Switzerland.

Newly manufactured US general aviation aircraft are usually flown by pilots who work for (or contract to) delivery companies.
As an example, Piper contracted a lot of their deliveries to a company who specialized in worldwide aircraft delivery pre-GPS. Anthony Vallone was one of their pilots and wrote Air Vagabonds which clarifies the dangers of flying small GA aircraft solo to various parts of the world.
Some companies provide delivery flights to their region for used and new GA aircraft. Clamback and Hennesey are notable for to/from Australia deliveries and have had to ditch in a near new Cessna 182 due to engine failure.
Atlantic crossings now mandate IFR and so VFR only aircraft are more likely to be container shipped. However Vallone's book details temporary fitment of nav/comm to comply with over ocean requirements like HF radio.

All the new aircraft deliveries I have been involved with were done by the buyer or the leasee. The normal process involves a physical inspection of the aircraft, paperwork, accessories, making sure the correct documentation is in hand, as well as one or more test flights to assure aircraft performance. In every delivery I have accepted, there is usually a squawk list, and the manufacturers are great at performing seeming miracles overnight. It is not uncommon that there is a couple of days of squawks. I often invite a factory test pilot along on the flights, as that helps identifying issues.
Some of the things I check include the rigging and trim of the aircraft, the power plant performance, the radio installations (which can require some coordination when picking up a plane mid-continent and testing HF), the autopilot systems, and the ECS.
Funds are transferred and paperwork is filed, and a flight to the destination is accomplished. Normally close fuel and power plant monitoring is done for that flight, and things like WX radar, strike finders and other avionics are extensively run.
If we don't have someone who has significant experience in the aircraft, we take training at a place like Flight Safety, in a simulator. Training is normally classified as initial or recurrent. The training outfit can tailor the training to include the specific equipment and engines that are included in the delivered aircraft.
The bulk of the aircraft I have personally accepted of delivery on are turboprops and jets, but it also includes a few piston aircraft. Some local flight schools, charter and FBOs have hired me to accept delivery of aircraft for them.
In my opinion the acceptance of new aircraft is more than just kick the tires and ferry the aircraft. It is a through systems checkout, and verification that all documentation is in place, cosmetics are good, and so, verifying that the end user receives a plane which is unlikely to have any issues, and that it performs as advertised.


text:
What is the appropriate fuel tank selection to land a 172?
On a recent checkout on a C172 I was told to select "fullest tank" as opposed to "both" that I have been doing for years. Given the aircraft is high wing (gravity feed) with no auxiliary fuel pump there should be no chance of sucking air.
Anyone know the correct selection?

What is the model and year? E.g. Cessna 172N 1977 has a special checklist and may be somewhat different than other models manufactured in different years. I would advise that you purchase a Pilots Operating Handbook for the relevant aircraft to find checklists/standard procedures.

That was bad advice.  The high-wing Cessna should ALWAYS be on BOTH for take-off and landing.  It would be good for that CFI to be corrected.

Welcome to aviation.SE!

You should check your POH but it may just be that the instructor in question was recently flying a lot of Pipers and it was force of [bad] habit.
This POH for the 172S is in agreement with you.

BEFORE LANDING
....

Fuel Selector Valve -- BOTH.

You should consult the checklist in the POH that is with the airplane in question to be sure.

I agree, I've never selected anything but both in a c172, or had anyone say you should do otherwise.

Appreciate that Dave, as it happens the operation have four Robin DR400's, two PA 28's and access to one C172. I will gently mention the "both" requirement next time I visit (as I'm reading the POH)

The only time I ever selected anything but "both" in a 172 is the one time I (foolishly) took off with a fuel imbalance. But even then, it would have equalized under "both".

Yes, the fuel selector typically must be selected to "Both" for takeoff and landing.
The Cessna 172 Type Certificate Data Sheet (TCDS) requires a placard for most early serial numbers (all models through S/N 17265684 except 17261445 and 17261578). This placard is to be located forward of the fuel selector valve and must state:

Both tanks on for takeoff and landing.

Note that this placard is required by certification for airworthiness, constitutes a limitation, and is to be followed by the pilot. See 14 CFR 91.9:

§91.9   Civil aircraft flight manual, marking, and placard requirements.
  (a) Except as provided in paragraph (d) of this section, no person may operate a civil aircraft without complying with the operating limitations specified in the approved Airplane or Rotorcraft Flight Manual, markings, and placards, or as otherwise prescribed by the certificating authority of the country of registry.

The TCDS only covers C172 models through C172Q and the S/N statement identifies the placard as a requirement only for models through C172M. (The two S/N exceptions are C172N models.)  The C172R and later are under a different TC.

Correction to my comment.  The later models are under the same TCDS.  It's just that you need to get TCDS 3A12 Rev 84 to see them.  In any case, the placard requirement  only applies through the M models.

@Gerry That is true, because the later models do have an electric fuel pump


text:
How to select a Lead In Fighter Trainer in the presence of both single engine and twin engine fighter jets?
A major part of fighter pilot training is learning the handling of the aircraft itself. On the other hand, automatic controls on modern fighter jets take away a lot of the pain and hassle. I am curious about the extent to which such ease of use plays a role in choosing the Lead In Fighter Trainer (LIFT) platform for an airforce.
Usually, it is assumed that the manufacturer supplying fighter jets will also supply the LIFT platform. But an airforce could buy jets from multiple vendors. It would be extremely cost ineffective to buy a different LIFT platform for each type of fighter jet. So airforces should try to standardize the LIFT platform they use.
Assume an airforce buys both single and twin engine fighter jets, from two different manufacturers. Neither aircraft has a twin seater version, so the first time pilots fly in them, they don't have an instructor sitting behind them giving instructions. Obviously, the aerodynamics and general handling of a twin engine fighter jet ought to be quite different from a single engine fighter jet. Now in making a decision on standardizing the LIFT platform, would this airforce take into account the presence of both single and twin engine fighter jets in its inventory? Would it procure two different LIFT platforms, one for training pilots towards single engine fighters, the other for training pilots towards twin engine fighters? Or does it make any practical sense for the airforce to choose only a single engine LIFT platform, or only a twin engine LIFT platform? What would be the pros and cons of such a decision?

I am not from the army, but I'd assume the trainer is to prevent the pilot from killing himself very fast in a very expensive airplane while learning how to fly. And it's cheaper to fly it for sure. (Some armies use even gliders for the start). The trainer just should have similar handling characteristics as a fast jet. Anyway the pilot will need to go through "type rating" and really train with an airplane he/she will be using.

There is no 8-engine jet trainer for B-52 pilots.

@GabrielVince the question is for that phase of training where the pilot has graduated from basic and advanced flying using basic trainers and has to convert to jet fighters through a LIFT platform. I'll edit the question to reflect this.

@DeepSpace the question is specifically about fighter jets.

The pilot will always go through transition training in the assigned aircraft prior to deployment. Depending on the aircraft assigned, this can range from a pretty short to fairly long training period.

@RonBeyer not all fighter jets come with a LIFT variant. In such a case, the Air Force will need to select a different LIFT platform. So the question remains, why/why not they would select a LIFT platform with the same engine configuration.

@DeepSpace So? The pilots surely train on a multi-engine plane before being sat in a B-52.

@AviationCurio Welcome to Aviation.SE! Can you please update your title so that it is a (grammatically correct) question that covers the general gist of your post in one sentence. See this meta discussion.

"Assume an airforce buys both single and twin engine fighter jets, from two different manufacturers. Neither aircraft has a twin seater version" examples of such aircraft?

Fighter lead-in isn't about becoming an expert in the training jet, it's about learning the fundamentals of flying tactical aircraft -- air combat maneuvering, strafing, bombing, etc.  So the difference between the aircraft flown in LIFT and the aircraft that the pilot will go to next isn't all that important.
I've never heard of any issues the US Air Force had with students flying AT-38's (2 engines) in fighter lead-in training then going to F-16 training.  The unique aspects of operating the single-engine F-16 are all covered during the F-16 course, and there are LOTS of differences between that and the AT-38.  Removing one of those differences, the # of engines, wouldn't be worth adding a whole new aircraft to the LIFT course -- a very expensive proposition for negligible gains.
So no, the number of engines in the eventual aircraft vs in the LIFT trainer is immaterial.

The F-16 has a two-seat version that can be used for operational conversion. I want to know about the case where there is no two seat version of the aircraft available.

@AviationCurio your question focuses on # engines, hence the answers do the same. if you care about the # seats, ask a different question. (but I am still not sure what you really want at this point)

@Federico, please re-read my edited question carefully. If a two seat version is available for an aircraft, it is obvious that operational conversion would be easy and the LIFT platform doesn't matter much. If a two seat version is not available, would an airforce try to match the number of engines more closely between LIFT and operations?

The answer to your question is "No"

does the number of engines needs to be the same as on the Lead In
  Fighter Trainer?

No.  It does not need to be.
I'll offer two examples.
The USAF used the T-38 pilot (twin engine) as the advanced jet for pilots who then flew F-16's(single engine) and F-15's(double engine) for 30+ years.
The USN used the TA-4J(single engine) to train jet pilots who F-8's and A-7's(one engine) and F-14's(two engines) for decades.
How many engines are in the training aircraft does not drive how many engines a pilot flies in front line aircraft, and vice versa.  How many engines are on a given jet aircraft is driven by the intersection of requirements, performance, and host of other factors in the development process.
A further example is the Hawk to Tornado progression in the RAF.
Now that your question has been changed, the question has to be called out as incorrectly framed.  There is an entire phase of conversion training that is covered by high fidelity simulation; a pilot transitioning from a training jet into a fleet jet first goes through extensive systems and basic performance training before taking a jet into the air.  Unless you account for the impressive advances in flight simulation for jet training in your question about how to get from one jet type to another, you are missing the point.
Again, the number of engines is not a major issue at that point in a pilot's development: it becomes a part and parcel to the aircraft systems and procedural knowledge imbedded in the training syllabus for a given type.

F-16, F-15, F-8, A-7, and Tornado all have a two seat version available that can be used for operational conversion. What about the case where there is no two seat version of the aircraft available?

The number of seats isn't what the question was originally about, it was the number of engines. Given the state of the art in simulation, for the past 30 years, I think your question misses the point.  Once you develop a certain level of mastery, your course conversion begins in high fidelity simulation and then you fly the aircraft.


text:
Can a flight instructor without instrument rating legally provide instrument training?
In the US the FAA requires student pilots to receive at least 3hrs of instrument flight training.
Can a flight instructor that does not hold an instrument rating legally provide a private pilot student the 3hrs of instrument training?

Don't all CFIs have an instrument rating? Perhaps you are referring to a CFII?

No they do not...

According to 61.183, they do. Except for a sport pilot instructor.

That's only if applying for... "(iv) A flight instructor certificate with an instrument rating." This question is for a flight instructor that has not applied for or received a instrument rating.

@MikeBrass No, not all airplane instructors have an instrument rating, but having an instrument rating is currently a prerequisite to apply for a flight instructor airplane certificate.  Back in the 90's the rule changed to make it a prerequisite, so it is possible that some old-timer is out there somewhere who is a CFI and is grandfathered in under the old rule with no instrument rating on his pilot certificate (much less his instructor certificate).

Long story short, a CFI without an instrument rating can provide training on the instrument flying required for a private certificate only. To provide instruction on the use of instruments for an instrument rating, a commercial certificate or an ATP certificate, the CFI must have an instrument rating.

You can read all the details in the Grayson (2010) legal interpretation and the FAA apparently revised 61.195 in 2009 to make this whole topic 'clearer':

§61.195   Flight instructor limitations and qualifications.
A person who holds a flight instructor certificate is subject to the
  following limitations:
[...]
(c) Instrument rating. A flight instructor may conduct instrument
  training for the issuance of an instrument rating, a type rating not
  limited to VFR, or the instrument training required for commercial
  pilot and airline transport pilot certificates if the following
  requirements are met:
(1) Except as provided in paragraph (c)(2) of this section, the flight
  instructor must hold an instrument rating appropriate to the aircraft
  used for the instrument training on his or her flight instructor
  certificate [...]

As the interpretation explains, the instrument training requirements for a private certificate are very general (61.107 and 61.109): "basic instrument maneuvers", " control and maneuvering of an airplane solely by reference to instruments". But the commercial and ATP requirements are much more specific (this is from 61.129): "attitude instrument flying, partial panel skills, recovery from unusual flight attitudes, and intercepting and tracking navigational systems". For that reason, CFIs who provide instruction for the private requirements only do not need an instrument rating.
Practically speaking, I've never met a CFI who didn't have an instrument rating. I'm guessing that a CFI without one would have limited value for employers and might even have issues with insurance.

The relevant part is “instrument rating appropriate… on his or her flight instructor certificate”. You can’t get an CFI without a commercial and instrument rating. So in order to give loggable instruction in a multi-engine plane, you must have your CFII and MEI. Single engine—CFII.

@JScarry would find it very strange if I found my IR instructor didn't have an IR himself...

@Pondlife - Thanks for the reference. I knew the correct answer but could not remember or find what or where the issue was that caused it to be clarified or updated. It makes sense that a CFI can give all appropriate training for a PPL.

Some of these rules have changed historically.  I believe that there didn't used to be a requirement for a instrument to get a CFI, and those "old-timers" can continue to instruct.  I know someone who got his CFI at 17 years old, but could not get a commercial yet.  At the time the FAA wasn't really sure what to do with him and he turned 18 and got his commercial before it was all worked out...Since then the regs have change to require a commercial, and he claims that this was his fault.

@jwenting Unless I am completely misreading §61.183   Eligibility requirements. it is not possible to get your CFI without an instrument rating.

It's what @Pondlife says -- the regs changed. When I got my CFI around 1990 you could get a CFI without an IR, though it wasn't very practical and I guess the FAA thought so also.

Helicopter CFIs are not required to have an Instrument Rating.  They may also provide training for the Commercial Helicopter rating (it,and the Pvt Airplane training; is not 'instrument training' as defined by the FAA Legal Dept.  Pvt helicopter pilots are not required to have training on instrument control.

You may add sources and links, possibly restricting this answer to some jurisdictions.


text:
Are the ICAO phonetic numbers used anywhere?
I ran across a table of ICAO (NATO) approved phonetic number pronunciations. As early as I can remember (50+yrs) in the United States "nin-er" is the only one I ever remember hearing in aviation and I don't recall hearing it in the last 30yrs. I recall hearing "Fife" but I don't remember where - perhaps ham radio operators.
I have never heard "tree" (three), "Tousand" (thousand), or "Fower" (four). If I heard ATC say, "maintain 'climb to nin-er humndred'", I would be very surprised. And if they said, "maintain 'tree tousand'", I would think they needed retesting for ICAO English language requirements.
Is there any country, military, or agency that regularly uses the full ICAO (NATO) approved phonetic number pronunciations? Is it taught to any pilots?

source

I was taught to say "fife" and "nine-er", but not "tree" or "tousand".

Where and when?

I was taught at KGRB about 5 years ago.

As the answers & comments come in and we get a better international understanding, I wonder if this has anything to do with proximity to Canada (or even the east coast / regional)?

I was tought “niner”, “tree” and “tousend” in Germany. But I usually use just “niner”.

If you've never heard "tree", "tousand" or "fife" then you should listen to the controllers in Dublin, Ireland (EIDW) on liveatc.net some time :-)

@RonBeyer - If you're still in the area, we're neighbors!

@SteveV. Indeed I am, my aircraft is collecting dust in a hangar in the north T's.

@David Richerby, an example of what I am talking about in the other thread...

Is there any country, military, or agency that regularly uses the full ICAO (NATO) approved phonetic number pronunciations? Is it taught to any pilots?

Yes, pretty much every country in the world. As you mostly have experience flying in the USA, where the native language is English, you may not be used to hearing these pronunciations so much. People whose native language is English tend to pronounce words [and numbers] as they would in normal speech. In most of the world, however, English is by no means the native language, so controllers and pilots alike will use the pronunciation guidelines created by ICAO to ease understanding across multiple dialects and accents.
As an example, the Danish aviation regulations has an exact copy of the table you present in your question, and it is used by everyone.

Aside from NIN-ER, all of these phonetics just simplify the standard English pronunciation to something easier for people who don't speak English fluently. For instance, many other languages don't have a TH sound, yet AFAIK all have a T sound.  In practice, fluent speakers will generally use the standard pronunciation out of habit, or they speak so quickly you can't tell either way so it doesn't matter.
I have noticed that, at least in the US, ATC will ofter mirror incorrect phonetics. I slipped one time and checked in as NINE AIT NIN-ER, and they actually replied with that. Another (old-timer) pilot always checked in as FOUR TWO SUGAR (rather than SIERRA) and they'd go with it every time. I think I've heard them mirror FOX (no TROT) and POP (vs PAPA) too. I wouldn't recommend that sort of thing for non-fluent speakers, though.

Our first response should mirror your identification exactly, and subsequent calls should use proper phraseology (.65 2–4–20). Of course controllers can get sloppy just as pilots can.

Anecdotally:I have personally heard and used every phonetic pronouncition on that list with the exception of 'TOUSAND'. I have been flying professionally for the past 20+ years in North and Central America as well as the Atlantic and Caribbean. So, is it still being used among ATC and pilots?. Yes. Is it widespread? That has not been my experience operating primarily near the United States. A sidenote on ZERO, I frequently hear 'ZE-RA' over the midwest U.S.

The FAA publishes the Pilot's Handbook of Aeronautical Knowledge to provide a guide for pilots. In Chapter 14 (Airport Operations) it says:

ICAO has adopted a phonetic alphabet that should be used in radio
  communications. When communicating with ATC, pilots should use this
  alphabet to identify their aircraft.

The table you posted, along with the pronunciation of the phonetic alphabet, is included for reference, except the hundred and thousand entries.
FAA JO 7110.65 provides the requirements for air traffic controllers, which includes the same table.

2−4−16. ICAO PHONETICSUse the ICAO pronunciation of numbers and
  individual letters.

My question is about it being used, not if it existed in an official capacity. At least in the United States, it does not seem to be used anymore. From 1975-1985 I owned a C-172 with the last three letters "09R". For the first few years I would occasionally hear "zero nin-er romeo". By 1985 I never heard "nin-er" anymore.

@jwzumwalt So are you just looking for everyone to post their own anecdotes?

"Is there any country, military, or agency that regularly uses..."

@jwzumwalt what's the standard of "regular use" you are looking for?

I agree that posting the regulations doesn't answer the question of what the actual use is. There may be a better way to answer this question than anecdotes.


text:
What are the limiting factors for high altitude planes (e.g: U2 or SR71) preventing them from going higher?
I'm curious as to why planes like the U2 Dragon Lady and the SR71 Blackbird couldn't fly higher. What physical constraint set their operational ceiling?
Pilots wore spacesuits, so that wasn't the limiting factor.  Was the air too thin to give enough lift? Was there not enough oxygen for the engines? Some other reason?
EDIT: My question is specifically about planes designed for high-altitude flight, not for general aircraft. To narrow the scope of my question, consider the SR-71 as the prototypical example. What set the operational ceiling of the SR-71?

Possible duplicate of What determines the maximum altitude a plane can reach?

Not duplicate. Edited question to narrow scope.

Even with your narrowing, I don't see how the other question would not apply here, tbh. Physics is the same for all.

@Federico The other question offers 5-7 possible limiting factors. My question is asking which one of those was the limiting factor for the SR-71.

Maybe a dupe in the case of the U-2 (limited by low IAS / high Mach #), but almost certainly NOT a duplicate with regard to the SR-71.  As a first guess, I suspect that aerodynamic heating may have been part of what limited the SR-71 from flying higher/faster, but I'd be interested in an answer more informed than my guess is. Good question, IMHO.

@Ralph J, the max cruise limitations on the SR-71 are predominantly powerplant and heat, but the altitude limitations as far as I know remain classified.  Inlet issues are probably primary limits at 3.4, but the A-12 had a flight with higher speeds (and was lighter).

The A-12 was also slightly shorter with the same basic shape, thus almost certainly less drag at the same speed.

The limiting factor for subsonic aircraft, including the U-2, is well explained here.
For supersonic aircraft this answer simply says the limit is "a combination of wing loading and maximum speed". If you look at the flight envelope of the SR-71 below, it becomes clear that more altitude can be best bought with more speed.

SR-71 flight envelope (picture source). Tower buzzing at Mach 3 is clearly impossible.
Supersonic speed limits

Intake design: If the kinetic energy of the flow cannot be efficiently converted into pressure in the intake, thrust will suffer and will drop when the flight Mach number is increased beyond the limits of the intake.
Airframe efficiency: If the leading edge sweep of flight surfaces is not high enough to keep those leading edges within the Mach cone, drag will rise and limit the top speed of a design. The desire to reach Mach 2+ speeds was the driver for the many swing wing designs of the 1960s.
Compressed gas temperature: Once the compression heating in the intake brings the gas temperature close to its dissociation temperature, the chemical energy in the fuel cannot be fully converted into heat. This reduces engine efficiency and is the reason for supersonic combustion in designs for speeds in excess of Mach 4 or 5.
Aerodynamic heating: Metals and composites show decreasing strength with increased temperature. Fly fast enough for some time, and the structure cannot tolerate the flight loads, even if dynamic pressure is kept constant.

The order in which I listed those limits ranks them with increasing speed. Once you move beyond Mach 1.6, every consecutive tenth of the top flight Mach number must be bought with increasing expenses and compromises. Going beyond Mach 5 with current technology will only be possible with rockets, so those designs quickly become low-orbit satellites. In the end, it is simply not worth it to push the limit yet further.

EDIT: It seems the answer is not explicit enough. If we try a thought experiment and modify the SR-71 to reach higher altitudes, the possible options are:

Just pull on the stick: This helps in the short term, but flying stationary at lower density would require a higher lift coefficient and a higher angle of attack. This would lower the overall L/D of the plane and slow it down because the engines could not develop sufficient thrust.
Increase engine thrust: This could be tried in flight by advancing the throttles at top speed, and the aircraft would accelerate. This would quickly exceed the limit of the compressor inlet temperature, though, leading to a shorter life time or even damage of the engine's hot section. Next, range would suffer due to the higher fuel consumption. If the engine is improved by using better materials, a moderate increase in cruise Mach and, consequently, flight altitude is possible.
Lower wing loading: A lighter aircraft can cruise at a lower density, all other parameters being equal. At the end of a trip the SR-71 could reach the highest altitude, just like any other plane. Structural changes to lighten the structure beyond removal of all reconnaissance equipment, however, would have only limited potential: The SR-71 was already designed efficiently, so there is very little potential for weight savings without compromising structural strength. And removing the cameras and side-looking radars would strip the plane of its operational value.

Excellent, well-sourced answer. However, it only half-answers the question. You established that the SR71 couldn't go higher because it couldn't go faster. Why did it have to go faster in order to go higher? Was there not enough lift at lower speeds? Not enough air for the engines?

Interesting answer on speed, but OP asked about operational ceiling.

@Nelson: We here frown on copying other answers into a new one, and prefer linking. Read the linked answers. If this still does not answer your question, you are free to post a new one. Make sure to explain why the other answers could not help.

@PeterKämpf I'm not sure what you mean by "copying other answers into a new one". What is it I'm not supposed to do? I don't mean to cause any trouble around here :)

To reduce wing loading (def: weight divided by wing area), you could decrease the weight, or you could increase the wing area. Could hypothetical solution #4 to the thought experiment above be "make the wings larger"? I suppose that could add some other issues (trade-off with increased drag, weight, etc), so it may be a bit too advanced of a discussion for a simple SE question...

@Nelson: That would be a new design. You can realistically only add area at the trailing edge, and now the plane will be nose-heavy. You need a new fuselage, move the wing forward, whatever. A new design, but not the SR-71 anymore.

@Nelson: If I copy my or someone else's answer to another question in my answer here, that is what I mean. You do alright.

Above 100,000 feet, there is almost no air at all, so no oxygen for air breathing engines to burn, and no air to produce lift or for control surfaces to react against.
In the 1960's, the USAF had two research aircraft that could exceed 100,000 feet. Might have had more, but these are the two that I remember:
The NF-104 could go slightly over 100,000 feet using a rocket engine above 70,000 feet for propulsion, and small reaction rockets to provide attitude control. It was built as a low cost X-15 trainer as its high flights simulated the X-15's operating characteristics.
The X-15 could go considerably over 100,000 feet, using a rocket engine at all times (after being launched from a B52), and small reaction rockets to provide attitude control.
Point being - by the time those aircraft exceeded 100,000 feet, they weren't flying. They were following a ballistic arc, propelled by a rocket, and kept aloft entirely by inertia, not lift.
So - why didn't the U2 and SR71 fly higher? One reason is - they would need rocket engines with oxydiser on board for propulsion, which is fairly short ranged, and very tempermental.
The requirement for rocket propulsion would negate the primary advantage of both aircraft: the ability to stay at high altitude for long periods of time.

A 1 m^2 opening at 100,000 feet crosses 29 kg per second of atmosphere at mach 5.  A 1m^2 opening at sea level at mach 0.5 crosses 208 kg/s.  That is "only" a factor of 10.  Getting an aircraft with a huge cone to get enough air and have it survive those speeds may be very tricky, but doesn't look physically impossible at 100000 feet.

In the case of the U-2 and the SR-71, the altitudes they operate at provide threat protection and more importantly, area coverage for ISR (intelligence, surveillance and reconnaissance) sensors.  Going to 100,000 feet does not provide a significant intelligence benefit, nor does it provide greater threat protection.
Service ceilings can be overcome by providing different powerplants. ECS (environmental control) can be redesigned (if needed) to handle higher altitudes.
Edit #2: In the specific case of the SR-71, the thrust capabilities and the wing surface area limited the max sustained flight. Practically, that was just below about 85,000 feet.  However in certain situations, altitudes above that were flown.
Edit #1: Above about 100,000 feet the atmospheric density drops off, which provides a practical limitation to airfoil and air breathing powerplant operation.
As I understand it, from working most of my career with SR-71, U-2 and satellite assets, the real issue is that there has not been established the need for aircraft to go higher, and therefore, there is no business case to develop aircraft to do so.

No greater threat protection at 100k vs 80k? Really??? An SA-2 / SA-3 / SA-whatever missile with enough energy to reach a Mach 3 target at 80k might have the energy to reach the same target at 100k, but its engagement envelope would be far smaller, and it would be easier to defeat with a small turn. There were reasons (satellites) the SR-71 wasn't kept around, but that isn't what this question is asking.

The question asked what the physical constraint is, and the reality is that there are not substantial physical constraints.  Rather they are need based constraints, and aircraft which would do ISR (the example class he mentioned) at 120,000 feet did not offer substantial benefit to justify the cost.  In other words, higher altitude flight is readily solvable, it just isn't economically justifiable.

Worth noting that the SR-71 routinely flew above 80,000, although as far as I know the max operational altitude remains classified. A friend who flew the NASA SR-71 aircraft acknowledged that the max altitude was still classified when assigned to that aircraft.

BTW, it is notable that the A-12 had a published service ceiling of 95,000 feet.  It weighed a little less than the SR-71, as the payload pods were configured differently.  NICE GIRL was a flyoff between both aircraft, and differentiated some of their capabilities. Weight is everything, and the YF-12 had a published ceiling of 90,000 feet.  The SR-71 was heavier than both, but accepted more useful payloads.

It might look like density drops of at 100k ft, but only when you plot it with linear scales. Here I have used the NRLMSISE00 model for a logarithmic plot, and as can be expected there is no change in the slope at or around 100k ft.

At 100,000 feet, there is about 1% of the density of sea level.  Linear / log, what's a few molecules among friends?  The reality is that for a jet engine to run in the 100,000 foot realm, it needs some kind of big compressor. I suppose that could be a big deployable compressor, or, like in the case of an SR-71, A-12, etc, it could be the compression caused mach level relative winds.


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Is commercial domestic service using foreign registry aircraft allowed in the USA?
I recently saw a domestic tour operator using aircraft with foreign registry. The pilots had U.S. CPLs. Can foreign-registered aircraft operate commercially within the U.S.A, in an operation where flights begin and end within the U.S.A.?

Yes, it's allowed under both part 135 (on-demand) and part 121 (airlines); 121.153 and 135.25 both have the same wording:

A certificate holder may operate in common carriage, and for the
  carriage of mail, a civil aircraft which is leased or chartered to it
  without crew and is registered in a country which is a party to the
  Convention on International Civil Aviation if— [...]

And US pilots may fly foreign aircraft within the US.

What about under Part 91?

@Mike The only way to fly charters under part 91 is if the customer provides the aircraft and hires the pilot to fly it. If the pilot or operator provides the aircraft - I assume that's the deal with the tour company you saw - then it's a 121/135 operation. See this question


text:
What are the standards on displaying Crew Awareness Messages?
Are there any standards on where in display Crew awareness system messages needs to be shown and how many messages at a time needs to be displayed. I checked SAE ARP4102-7 but I didn't find any guidance.

Yes, certainly there are standards for crew awareness messages. The number of messages displayed is normally limited by screen space allotted, which is may vary from around 5 to 15 messages  and when there is a 'spillover' the messages continue on the next page. The pages are selectable via a simple cancel/recall push button and may also automatically change as corrective actions are taken by the crew or the cause/fault ceases for whatever reason. There is Colour Coding, eg red for Warnings and amber for Cautions. Green and white are also typically used for normal but temporarily used systems eg 'Anti-Ice' or Passenger signs.
All the above describe some of the features of modern crew alerting systems, for details refer to the following document:
(You might find it useful to go to Appendix 5 (Definitions), right at the end of this Advisory Circular, before reading the main body of the document. Appendix 5 makes mention using diagrams as to where in the pilots field vision the visual alert should ideally be.)
Click here for the FAA AC 25.1322-1 'CREW ALERTING'
The above linked AC shows us acceptable means of complying with FAA Rule which is - 14 CFR Part 25.1322 reproduced below.

§ 25.1322 Flightcrew alerting. (a) Flightcrew alerts must:
(1) Provide the flightcrew with the information needed to:
(i) Identify non-normal operation or airplane system conditions, and
(ii) Determine the appropriate actions, if any.
(2) Be readily and easily detectable and intelligible by the
flightcrew under all foreseeable operating conditions, including
conditions where multiple alerts are provided.
(3) Be removed when the alerting condition no longer exists.
(b) Alerts must conform to the following prioritization hierarchy
based on the urgency of flightcrew awareness and response.
(1) Warning: For conditions that require immediate flightcrew
awareness and immediate flightcrew response.
(2) Caution: For conditions that require immediate flightcrew
awareness and subsequent flightcrew response.
(3) Advisory: For conditions that require flightcrew awareness and may
require subsequent flightcrew response.
(c) Warning and caution alerts must:
(1) Be prioritized within each category, when necessary.
(2) Provide timely attention-getting cues through at least two
different senses by a combination of aural, visual, or tactile
indications.
(3) Permit each occurrence of the attention-getting cues required by
paragraph (c)(2) of this section to be acknowledged and suppressed,
unless they are required to be continuous.
(d) The alert function must be designed to minimize the effects of
false and nuisance alerts. In particular, it must be designed to:
(1) Prevent the presentation of an alert that is inappropriate or
unnecessary.
(2) Provide a means to suppress an attention-getting component of an
alert caused by a failure of the alerting function that interferes
with the flightcrew's ability to safely operate the airplane. This
means must not be readily available to the flightcrew so that it could
be operated inadvertently or by habitual reflexive action. When an
alert is suppressed, there must be a clear and unmistakable
annunciation to the flightcrew that the alert has been suppressed.
(e) Visual alert indications must:
(1) Conform to the following color convention:
(i) Red for warning alert indications.
(ii) Amber or yellow for caution alert indications.
(iii) Any color except red or green for advisory alert indications.
(2) Use visual coding techniques, together with other alerting
function elements on the flight deck, to distinguish between warning,
caution, and advisory alert indications, if they are presented on
monochromatic displays that are not capable of conforming to the color
convention in paragraph (e)(1) of this section.
(f) Use of the colors red, amber, and yellow on the flight deck for
functions other than flightcrew alerting must be limited and must not
adversely affect flightcrew alerting.

thanks I went through the doc .But I didn't find how much screen space needs to be allotted or at a time how many messages needs to be displayed

I've now added the actual FAA Rule at the end of the existing answer, maybe that'll give you a better idea. It's about complying with this rule so as to satisfy the Certifying authority, and that does not necessarily mean defining the number of lines and display 'real estate' dedicated to it. see particularly (a)(2) and (c)(2) - what has prompted your query? The appendix 5, mentioned earlier, has diagrams showing where in the field of vision the alerts should appear. One manufacturer indicates 11 lines of messages.

@HariomSingh, why do you think a regulation should go into such detail? It specifies functional requirements. Plus additional requirements follow from those for non-normal procedure design, because the alerting needs to provide all the necessary information for all imaginable non-normal procedures. But how much that is depends on what systems the aircraft has.


text:
How much electrical power is available in a Gulfstream G550 and from which power sources?
I'd like to understand what electrical power sources are available (engines? APU? GPU? Other?) on a larger jet like the G550, and how much power they can provide, depending on whether the airplane is flying at cruise speed or on the ground. I'm curious about how much electrical load can be added to the aircraft and how.

There are some answers to common electrical questions about the G550 here according to them the engine integrated drive generator (IDG) unit delivers 40KVA, 400HZ, 115V; they don't list a power factor but lets be conservative and assume .8 (it must be between 0 and 1). This would result in 32 Kilowatts per IDG. So you have 64 Kilowatts at your disposal. The minimum load will depends on the avionics installed and can vary from plane to plane. At night load will be increased as a result of the use of interior lights as well as landing lights during takeoff and approach. Your load will be highly variant on the interior of the aircraft. As this is a luxury plane there could be a whole host of things inside like TV's, lights, kitchen equipment etc. You can find specific equipment installations in the POH/loading info for a given airframe. You can find a nice breakdown of the G450's electrical system here.
As for how you can add it, you can simply add it as you would add any accessory, to the main bus (by an A&P of course). You will need to make sure the item can be added to the craft and in some cases there may be a stipulation along the lines of not using it during takeoff or landing. The amount of load will vary by aircraft and dependent on what else is installed.

I'd like to understand what electrical power sources are available
  (engines? APU? GPU? Other?)

The engines (while running) are generally the main source of power. The APU is often used on the ground when the engines are off but the plane needs electronics on and can also serve to help start the engines. It does appear the G550 has an APU. According to this data sheet the G550 runs a Honeywell RE220 APU that can output 45 Kilowatts. According to the site it will operate up to 37,000+ Ft. so it in theory could be run for the duration of a flight.
A GPU is only available on the ground and only at airports that have them. Their output varies widely and a large variety of types may be available at any given airport.

Thanks a lot this is very helpful! I looked at your links and I also noticed there's a mention of "main" buses and "essential" busses. I guess the essential one is for all the most important functions that keep the jet flying. How does this work? Is a fixed amount of power usually allocated to the essential bus? Finally, do you know where I can find similar info for other jets, such as Citation X, Hawker 800 or Global 5000? Thanks again for all the invaluable info!

Based on these answers it sounds like the essential bus drives things necessary for flight and most importantly can be driven by some of the emergency power sources in the event of a generator failure etc. Depending on the source the bus should always be able to drive the minimum systems to fly the plane. If the main power units are working there will be more than enough available on the bus.

As for finding this info on other planes, try a search for wiring diagrams, electrical layouts etc (thats how I found the stuff linked above). You could also reach out to an A&P or the the company them selves for more info. Some (not all) POH's can be found online. A search for "{airplane type} POH" should give you what you seek. If you have a specific question on installing a particular component you may want to ask it here and see what people say.

Awesome, I'll have a thorough look into all of that. Thanks for your help!


text:
Do pilots have the ability to bypass customs when utilizing jump-seat privileges?
I wonder if anyone can help with a hypothetical question. Its for a novel I am researching
All passengers with a ticket for a flight will pass through normal passport controls but I am told that Pilots can jump a flight if theres a spare seat. I know it might be outside of procedure but...
Is it feasible that he might join his buddies and get on the plane with them and avoid the official record of him entering and leaving another country say between the USA and Canada?

Pretty sure that pilots have to cross customs too.

Yes I thought they might, I am examining the possibility of a person actively skirting the system by some form of skulduggery, but thanks for your help

There is a little problem: Insurance. You cannot board a flight without knowledge from the company and a flight ticket, even if you don't pay the trip, else the company would not be covered by insurance in case of accident. Also the company needs to know how many souls are onboard for the same reason.

All flight crew go through the same customs, immigration and security screening as everybody else, dead-heading or not. They sometimes get their separate line, or are sometimes allowed to just cut in front of "normal" people, but it's the same process.

Back in the 1990s I was a captain for one of the so-called ex-CIA airlines, airlines and facilities that had been sold to private individuals for pennies on the dollar. We flew 747 freighters all over the world. Twice, when presented with the weight & balance paperwork, I was told that upper deck ACMs were deliberately not on the weight & balance or the crew manifest and would not be accompanying us through customs and immigration. This was accepted as normal. I wrote an unpublished novel that involved moving people illegally by air across borders. It's at terryliittschwager.com/novel.php.

+1 for doing your research before writing your novel! Best of luck to you. If he hadn't died in 2008, I might be tempted to accuse "Michael J" of being John Michael Crichton - and that would be a good thing!  ;)

Even astronauts

You may also be interested in our sister sites, [travel.se] and [worldbuilding.se].

Just to put down as an answer what has been pretty well covered in the comments...
All pilots, jump-seating or not, will still clear customs.  They may have a separate line, but there will still be the normal record of their entry.
Beyond that, the airline absolutely knows who they let on the jumpseat for each flight -- so "no record" won't really happen in any event.

Not anymore, anyway.....

Do they get stamped each time ? Sounds like the passport would be filled very quickly

Some country does not stamp visitors passport anymore. If I remember right, Hong Kong is an example.

I have flown numerous times on jump seats. I just enter the airport as anyone else, report to the check-in desk and wait there until check-in closes. With the check-in closed the phone the gate and ask for the number of seats available. With all the seats taken they ask the captain if they would allow the jump seats to be taken. Check-in and Security is done as with a regular ticket. I also do not fly as airline staff and have to que in the normal lines and can't take the crew shortcut.
On my boarding class the booking/travel class is different.


text:
Why is there a difference between military parachutes and those used for skydiving?
A couple hours ago I was watching a youtube video where skydivers jump using the skydive parachute, and after that, a military training where the soldiers jump using "old" type parachute, the dome shaped one.
Why is the military using the dome shaped one?
The skydive parachute is smaller, and more compact, and has manoeuvrability (as I can see, I'm not an parachute expert).
Is it because of protection against enemy fire? Since it's larger it can take more damage of enemy firepower, or what?

From what I learned, different types of parachutes don't make them 'old' or 'new'. They are used for different purposes.
For example the dome shape parachute is usually used for static line jump where no maneuverability is really required. They drop vertically relatively to the plane path when air friction is negligible.
The other kinds are usually used for special forces because they always do jumps like HAHO (High Altitude [Jump] High [Altitude] Open) when the location they jump is outside their country's territory, and infiltrate by air so the plane is out of the radar/SA missile range. They have to have the ability to glide on a long distance.
Another case is they have to have the ability to change the trajectory or precisely land in the drop zone. So maneuverability is a must.
Size differs for different manufacturer and different specs. Even though the dome type parachute is relatively larger, the chance of getting hit is similar with other types as you don't have much speed and you can't do crazy high G turns. You really can't avoid any attack towards you unless you have superhuman reactions and the sixth sense.
To conclude, different types of parachutes are used for different purposes in different scenarios.

Welcome! Very interesting answer.

Ok, that's mostly advantages of the paraglide (rectangular, controllable) type. Yes, it is not always used. So what about the advantages of the round type? (AFAICT, the main advantage is that for the round one all you need is a bit of training on the landing and you are good to go while the controllable requires extensive training in controlling it).

They are cheaper because of the simpler control and as I mentioned they can go straight down relatively to the plane speed. The advantage of this is to control the drop zone of a lot of soldiers for the commander. As you mentioned round one requires less training and the fact that they are simpler, they have less chance to mess up with the controls and land on their dedicated drop zone.     You don't want a bunch of soldiers to land with miles of separation and spend a few hours gathering them. In case of a quick response mission, the outcome will be disastouros.

I think the simplicity is key. All you need to know for a static line jump is how to fall out of the plane (trivial), bend your knees and roll when landing (everybody who has ever jumped off something higher than a chair knows that), and separate yourself from the parachute (the only bit that really requires training, and it's not that complicated – when in doubt, use your knife). For a steerable parachute, you need to learn, well, to steer it, and you need to learn to navigate (so you know where to steer to). More complex to learn plus more complex equipment == more to go wrong.

Dom-shaped parachutes are steerable, just not as much as high-performance chutes. You need to be able to steer to avoid obstacles on the ground.

A couple hundred paratroopers steering their glide chutes around, flying into each other, getting their chutes tangled and plummeting to the ground. Now that sounds like fun.

Would there be a difference between a HAHO chute and a HALO chute?

I would guess that the larger area of the "traditional" round parachute is also able to support/slow a greater amount of weight than a performance chute would. This is a huge advantage when you have 175lb+ troops laden with an additional 50-100 lbs of gear falling out of the sky and wanting to land uninjured.

The impact force is actually higher when landing using a round parachute according to newton's third law

@Hezzte eh, I'll need some math to be convinced of what you say in your last comment

Total downward force = ( Massxg(9.81) - upward force(air resistance by the chute)

To make a "traditional" round parachute practical, it's air resistance should not be excess. But a glide chute can produce lift while gliding making it possible to control the downward force up creating an opposing upward force. That's why you can minimize the impact force by creating an upward force while using a glide chute. So the impact force will be relatively higher while using a round chute. @Federico

@FreeMan, no, the larger size of round chute is because it generates less upward force (it is considered drag, not lift) per unit area. You can design either for whatever weight you need by scaling it appropriately.


text:
What is the largest aircraft (by max takeoff weight) in which all engines are in the tail?
The largest one I'm aware of is the Il-62, with a whopping 4 turbofans at its tail. Max takeoff weight is 165 tons.
I actually don't care how many engines there are, as long as all are at the tail. I don't care what kind either, turbofans, turbojets, anything. Don't care if it's military or civilian.
Edit: Airbreathing engines only. The space shuttle and buran don't go above 109 tons anyway, but the criteria here is max takeoff weight and those rockets "take off" far too differently than airplanes.
I googled this of course, but predictably these kinds of "what's the biggest" questions with specific conditions attached are not well-known. I'm hoping someone will know of an example bigger than 165 tons.
The reason I ask is because I'm curious just how much engine weight can be put at the tail and still have a conventionally-shaped aircraft. I'm a little surprised at the Il-62, actually. Sooner or later, to keep the center of mass ahead of the center of drag, the wings have to move more and more back until suddenly you have a canard config where the wings almost operate like a delta where the ailerons are also elevons and maybe even flaps.

Well... Not quite an aircraft (it's ekranoplan) and not quite having its engines at the tail (its engine are at the nose), but this is too good to not mention: the Lun class ekranoplan - 8 turbojets, all in the very front. https://en.wikipedia.org/wiki/Lun-class_ekranoplan

How about the Saturn V? That certainly had all the engines in the tail... Failing that, the Space Shuttle is at  least more aircrafty.

@DanieleProcida The shuttle is indeed more aircrafty, but it never had its engines running when flying as an aircraft.

There was a Buran test bed with 4 jet engines in the tail (OK-GLI, https://en.wikipedia.org/wiki/OK-GLI), but MTOW in that configuration is below 100 tons.

What about blended wing body planes with the engines at the rear? Or are you only interested in tubes with wings?

@Owen Those are fine but let's keep it to aircraft that have actually flown without crashing. I'm not aware of any flying wing, actually flying, that goes above 165 tons.

@DeepSpace That goes airborne and breathes air so I consider it an aircraft. Ground effect doesn't disqualify it. Some early flights, I think even the Wright flier, were also pretty low and might've used ground effect, but that doesn't disqualify a flight. It's still lift after all.

@DanieleProcida Space shuttle orbiter is not more than 30 tons. I think I'm gonna edit the OP to only include airbreathing engines anyway. When the criteria is max takeoffweight, rockets "take off" very differently from planes anyway.

space shuttle and buran don't go above 30 tons - Both maxed over 100 tonnes. Heck, the Shuttle could carry almost 30 tons to orbit.

@HephaestusAetnaean Darn, so much for my memory. Wikipedia says the shuttle's max takeoff weight is 109 tons. Astronautix.com says Buran's gross mass is 105 tons. Pretty hefty stuff.

I was thinking B-2 spirit but upon closer inspection the engines are mid wing, not at the rear. MTOW is 188 tons.

What about aircraft where the wing extends far enough back to include the horizontal tail?  Both the Concorde and Tu-144 have wings that extend so far back that the engines're at about the same longitudinal location as on an Il-62, and have MTOWs of 185 and 207 tonnes, respectively.

I think you've got it. Surprising to see how much larger it was than the VC.10.
There was a planned development of the VC-10 that used the VC-10 wing and tailplanes with a new double-deck fuselage. This VC-10 Superb (DB.265) had a planned MTOW of 174 tons.

Not that much larger (165 tonnes, versus 151.9 for the VC10-1101).

The B-1B has its engines behind the wing (at least in "wing-forward" configuration,) and a MTOW of 477,000 pounds, according to Boeing.

If B-1B counts, then the heavier Tu-160 would count too (275 tons/606,000 lb). But not really, they both have 'under wing' sort of configuration.